Metabolism in Rats - Pharmacokinetics of bisphenol A in neonatal and adult Sprague-Dawley rats

Author: Doerge et al.

Publication: Toxicology and Applied Pharmacology

Date: September 1, 2010

metabolism

This study concluded that BPA is efficiently metabolized by adult rats after oral exposure and, while neonatal rats are not identical to adults, they also have the capability to efficiently metabolize BPA. As a result of efficient metabolism, estrogenic effects from BPA are unlikely due to the very low levels of unmetabolized BPA in the body after oral exposure. Because BPA is efficiently metabolized after oral exposure, studies that expose animals by subcutaneous injection are of limited relevance to human health concerns that primarily involve oral exposure. Because of efficient metabolism and rapid elimination, BPA does not accumulate in the body.

At a Glance

What was tested?
Adult female rates and their offspring were orally dosed with BPA to determine how it is processed in the body (also known as the study of pharmacokinetics).
Findings
The study concluded that BPA is efficiently metabolized by adult rats after oral exposure and, while neonatal rats are not identical to adults, they also have the capability to efficiently metabolize BPA. As a result of the efficient metabolism, estrogen effects from BPA are unlikely to the very low levels of unmetabolized BPA in the body after oral exposure.
Study Limitations
Authors note that the levels of active BPA measured in the bodies of rats in this study are likely too low to cause health effects via traditional estrogen signaling pathways. However, the potential for BPA to impact alternative estrogen signaling pathway in infant rats “cannot be excluded.”
Importance
Because BPA is efficiently metabolized after oral exposure, studies that expose animals by subcutaneous injection are of limited relevance to human health concerns that primarily involve oral exposure. Because of efficient metabolism and rapid elimination, BPA does not accumulate in the body.